Durability and maturity are the primary factors NFL general managers must evaluate in assessing the draft value of Texas A&M quarterback Johnny Manziel, former Dallas Cowboys star quarterback and Pro Football Hall of Famer Troy Aikman said Thursday.

Speaking on KTCK-AM in Dallas, Aikman specifically questioned whether Manziel's smaller body could withstand the punishment NFL defenses will deliver, and whether the Aggies' third-year sophomore and 2012 Heisman Trophy winner will be the sort of quarterback clubs will want as a public representative.

"I think he'll be pretty good," Aikman said, according to The Dallas Morning News. "The concerns that I have would first of all, be his size. Can he take the pounding? I've never met him, so I'm not sure what his stature is, but he just seems like he's a pretty small guy, and maybe, I don't want to say fragile, but the punishment in the NFL could take a toll on him. So that would be concern No. 1."

Manziel is listed at 6-foot-1, 200 pounds, and suffered a few minor injuries as a sophomore after navigating his freshman season injury-free in 2012. If NFL clubs determine Manziel's career is at risk to be hampered or shortened by injury, that could have an adverse effect on his draft value. Aikman also brought up Manziel's maturity level.

"The No. 2 would be, not having sat and visited with him, how well can he be the face of a franchise? Is he mature enough to handle that responsibility? Is he going to commit himself to being a great NFL quarterback or are other things more important to him?" Aikman said. "If you can come out of those questions and say, 'Yeah, I believe he's big enough to withstand the punishment and I believe he is committed and he is going to do the right things because we're going to be paying him a lot of money,' then I think he's a first-round talent. I really do."

Manziel has been projected as a first-round draft pick, and at least half of the teams picking in the draft's top 10 choices have a need at quarterback, according to NFL Media's Daniel Jeremiah. More athletic quarterbacks are trending in the NFL recently, although not all have achieved success. Russell Wilson of the Seattle Seahawks is the best young example of a skillful runner making his way in the league as a quarterback. Former first-round draft pick Tim Tebow, by contrast, could not find his way to a roster in 2013. Aikman's evaluation of Tebow coming out of the University of Florida was a glowing one, according to the Tampa Bay Times.

"He can do it all," Aikman said in December 2009 prior to Tebow being drafted by the Denver Broncos No. 25 overall in 2010. "He's been doing the whole wildcat before it even became in vogue in the NFL. I don't know exactly where he's going to go or high he might be. But I'll tell you this. He's a guy I'd like to have on my team. And I think with his leadership ability and his athletic skills, a team can find a place to play him where he can make a real impact for an NFL club."

Tebow recently took a job as a college football analyst with the SEC Network but is maintaining efforts to make a comeback in the NFL, working with private instructors to reinvent the slower delivery that scouts marked as one of his drawbacks. Manziel, for his part, hasn't had his delivery scrutinized as much as his reckless style of play, and unwillingness to take a sack or throw the ball out of bounds on broken plays.

Nevertheless, Manziel was much improved as a passer between 2012 and 2013, increasing his touchdown passes from 26 to 37, completing a higher percentage of his passes (68 to 70 percent) and taking fewer sacks (22 to 19). Aikman saw that progress, and was especially impressed with Manziel's play against then-No. 1-ranked Alabama on Sept. 14.

"From what I've seen, he's a playmaker," Aikman added. "The criticisms I know coming into this year were that he didn't throw the ball as effectively as he needed to. I haven't seen him play a lot, but I saw him play against Alabama, I saw him play a couple of other times and he made throws that -- they weren't these schoolyard throws. They were in the pocket, getting the ball out, reading the defense. And I was impressed.

"So, with those questions, and the biggest one being the intangibles, I think he's got the chance to have a really big career."

Manziel threw five touchdown passes against the Crimson Tide in a 49-42 loss, and all five of them illustrated Aikman's point, being thrown from the pocket on different types of routes and in some cases, off multiple reads.